2156813547 has 24 divisors (see below), whose sum is σ = 3354981696. Its totient is φ = 1228884048.

The previous prime is 2156813537. The next prime is 2156813587. The reversal of 2156813547 is 7453186512.

It is a happy number.

It is not a de Polignac number, because 2156813547 - 2¹⁰ = 2156812523 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2156813499 and 2156813508.

It is not an unprimeable number, because it can be changed into a prime (2156813507) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 29868 + ... + 72150.

It is an arithmetic number, because the mean of its divisors is an integer number (139790904).

Almost surely, 2^2156813547 is an apocalyptic number.

2156813547 is a deficient number, since it is larger than the sum of its proper divisors (1198168149).

2156813547 is a wasteful number, since it uses less digits than its factorization.

2156813547 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42647 (or 42640 counting only the distinct ones).

The product of its digits is 201600, while the sum is 42.

The square root of 2156813547 is about 46441.5067262034. The cubic root of 2156813547 is about 1292.0248525909.

The spelling of 2156813547 in words is "two billion, one hundred fifty-six million, eight hundred thirteen thousand, five hundred forty-seven".